If $${({x^2} + {y^2})^2} = xy$$, then $${{dy} \over {dx}}$$ is

If a matrix A is both symmetric and skew symmetric, then A is necessarily a

Let set X = {1, 2, 3} and a relation R is defined in X as : R = {(1, 3), (2, 2), (3, 2)}, then minimum ordered pairs which should be added in relation R to make it reflexive and symmetric are

A Linear Programming Problem is as follows:

Minimize z = 2x + y

subject to the constraints

x $$\ge$$ 3, x $$\le$$ 9, y $$\ge$$ 0

x $$-$$ y $$\ge$$ 0, x + y $$\le$$ 14

The feasible region has